Nature Notes Unite Against Interloper

As you ride along some of our scenic routes where you used to be able to get a good look at the water, be it a pond water, the ocean, a bay, or a creek water, you will often find the view obscured by one of the world’s tallest grasses, the common reed, or phragmites. Linnaeus himself in the mid-1700s first described the reed and gave it its first scientific name, the binomen Arundo phragmites, one of thousands he created. Phragmites stems from the Greek for “growing in hedges,” and describes its tendency to form vegetative walls that block the view.
Such occlusive walls can presently be seen in all their summer glory in Montauk along Old West Lake Drive adjacent to Lake Montauk, along Industrial Road on the north end of Fort Pond, and around Tuthill Pond, just to the northeast of Fort Pond. They are also growing heartily around the back side of Fresh Pond in Amagansett, along Albert’s Landing Road, along Old Stone Highway bordering Accabonac Harbor in Springs, on the north side of Soak Hides Road at the south end of Three Mile Harbor, between Scoy Pond stream and Ely Brook Pond, along Alewife Brook Road in Northwest, then again, on both sides of Northwest Creek and on both sides of Little Northwest Creek as ones drives to the Sag Harbor Golf Course from Route 114 in Sag Harbor.
The State Department of Environmental Conservation says in no uncertain terms that we can’t touch these tall, thick hedges without a permit, which can cost up to $800 and take years to acquire. That’s because the state’s tidal and freshwater wetlands regulations, written in the early 1970s, considered phragmites, then known as Phragmites australis, to be a native wetland species ranking right up there with the likes of sacrosanct saltmarsh cordgrass and cattails. Since the early 1970s, this so-called native has been taking over wetlands throughout Long Island and much of eastern North America. It has shown itself to be a real bully, but not a “weed” because it was believed to be native, found in all of the lower 48.
Then along comes a young Yaley named Kristin Saltonstall in the late 1980s and early 1990s, who, using genomic analysis, discovers, “Hey, this thing isn’t native at all; it’s an immigrant from Eurasia.” Ha, ha, the thing we began to hate but couldn’t because it was as American as apple pie, was really a dreadful interloper from abroad. This same woman, now Dr. Kristin Saltonstall of the University of Maryland, went on to describe a native American phragmites, Phragmites americanus, with the help of fellow botanists, but it is very rare, having been overshadowed by the undocumented alien, a very close lookalike.
Arthur Haines’s “Flora Novae Angliae,” published by the Yale University Press in 2011, has finally put the nail in the coffin. You can tell the bad guy phragmites by its darker to grayish-green leaves, its dull, ridged stem joints (called internodes), and the many fine parallel ridges running along the stem from bottom to top. Aha, I thought, I bet what I have been looking at and scratching my head over for so many years on the South Fork and other parts of Long Island is not the native, but the evil intruder.
So on Monday I started in Montauk on East Lake Drive and made 13 stops on the way back to Sag Harbor along all of those roads and water bodies listed above to take samples from and photograph the different stands. Wouldn’t you just know it: All of the phragmites at the 13 different sites were Eurasian in origin. They all had those attributes described by Haines and Saltonstall. In other words, because we failed to look below the surface or couldn’t because of technical difficulties (DNA and other molecular analyses to differentiate plants is fairly new), we have been snookered by this wolf in lamb’s clothing, Phragmites australis.
While in Eurasia some natural enemies have been keeping it at bay, to the extent that it has even become rare in parts of Europe, here it shows no signs of faltering on its march to the sea. The only American phragmites I have ever seen was in Florida, but there are still small patches of it here and there in New England and northeastern Canada, say, Nova Scotia. Both species have a clever way of reproducing themselves, not so much by spreading seed, but by rhizomic extension, i.e., cloning, the way that American beeches, quaking aspens, sumacs, and a host of other native species choose to spread.
In this respect, the Eurasian species far outguns its American cousin. It can send it rhizomes out 20 to 30 feet over land until the tip reaches the water. The elongate rhizome can put up a shoot every six inches or so. The American version is not so greedy and distributes its offspring much more sparsely.
Phragmites isn’t all bad. It does remove nitrogen, which would otherwise enter the waterways, from the soil. On the other hand, the relationship between the native eelgrass and foreign phragmites is of interest and needs to be studied more. In those parts of the Peconic Estuary in East Hampton Town, wherever phragmites forms area-wide stands such as at Northwest Creek, Accabonac Harbor, and Fresh Pond, Amagansett, eelgrass has practically disappeared. Along the banks of Napeague Harbor and, to a lesser extent, along those of Lake Montauk, there is not much phragmites and eelgrass is still making a go of it on the bottoms of those water bodies.
On Monday, I started with East Lake Drive because it is the home of a pond built in 1910 on land donated to the Town of East Hampton. After the pond was done in early summer and the Eurasian phragmites began to make a serious comeback, I cut all of the phragmites on the north side of the pond on more than one occasion. I was proceeding according to a hypothesis recently construed by Karen Blumer, the Long Island author of “Growing Wild,” a book about getting rid of invasives and bringing back native plants on Long Island. The hypothesis simply states that you don’t have to replant with natives once you remove the invasives (or in my case, cut them to the ground); the natives will come back on their own. What did I find? Three years after my first phragmites cutting, and almost two years without subsequent cuttings, I went to look: “My God,” I thought, “Karen’s hypothesis seems to be ringing true.”
On the south side of Bond’s Pond, named for the man who donated the land, there was a magnificent hedge of foreign phragmites, while on the north side there were native sedges, rushes, verbenas, alders, goldenrods, at least 30 different native wetland and near-wetland species flourishing along with a few straggly phragmites of foreign extraction.
So let us not wring our hands about people cutting phragmites. They are freeing the wetland edges for the comeback of true natives such as the marsh hibiscus, blue flag, and other American pretties, and maybe in time our own Phragmites Americans. People of the South Fork unite: Hew down bad phragmites, free the wetlands from their stranglehold, validate Blumer’s hypothesis.